Effect of unweighting on skeletal muscle use during exercise

1995 ◽  
Vol 79 (1) ◽  
pp. 168-175 ◽  
Author(s):  
L. L. Ploutz-Snyder ◽  
P. A. Tesch ◽  
D. J. Crittenden ◽  
G. A. Dudley
Keyword(s):  
Lower Limb ◽  
Weight Bearing ◽  
Muscle Group ◽  
Mr Images ◽  
Cross Sectional ◽  
Quadriceps Femoris Muscle ◽  
Before And After ◽  
Exercise Induced ◽  
The Right ◽  
Femoris Muscle

Exercise-induced spin-spin relaxation time (T2) shifts in magnetic resonance (MR) images were used to test the hypothesis that more muscle would be used to perform a given submaximal task after 5 wk of unweighting. Before and after unilateral lower limb suspension (ULLS), 7 subjects performed 5 sets of 10 unilateral concentric actions with the quadriceps femoris muscle group (QF) at each of 4 loads: 25, 40, 55, and 70% of maximum. T2-weighted MR images of the thigh were collected at rest and after each relative load. ULLS elicited a 20% decrease in strength of the left unweighted QF and a 14% decrease in average cross-sectional area (CSA) with no changes in the right weight-bearing QF. Average CSA of the left or right QF showing exercise-induced T2 shift increased as a function of exercise intensity both before and after ULLS. On average, 12 +/- 1, 15 +/- 2, 18 +/- 2, and 22 +/- 1 cm2 of either QF showed elevated T2 for the 25, 40, 55, and 70% loads, respectively, before ULLS. Average CSA of the left but not the right QF, showing elevated T2 after ULLS, was increased to 16 +/- 2, 23 +/- 3, 31 +/- 7, and 39 +/- 5 cm2, respectively. The results indicated that unweighting increased exercise-induced T2 shift in MR images, presumably due to greater muscle mass involvement in exercise after than before unweighting, suggesting a change in motor control.

Effect of resistance training on muscle use during exercise

1994 ◽  
Vol 76 (4) ◽  
pp. 1675-1681 ◽  
Author(s):  
L. L. Ploutz ◽  
P. A. Tesch ◽  
R. L. Biro ◽  
G. A. Dudley
Keyword(s):  
Resistance Training ◽  
Image Contrast ◽  
Mr Images ◽  
Short Term ◽  
Mr Image ◽  
Cross Sectional ◽  
Neural Factors ◽  
Exercise Induced ◽  
The Right ◽  
Control Exercise

This study examined the effect of resistance training on exercise-induced contrast shift in magnetic resonance (MR) images. It was hypothesized that a given load could be lifted after training with less muscle showing contrast shift, thereby suggesting less muscle was used to perform the exercise. Nine males trained the left quadriceps femoris (QF) muscle 2 days/wk for 9 wk using 3–6 sets of 12 knee extensions each day. The right QF served as a “control.” Exercise-induced contrast shifts in MR images evoked by each of three bouts of exercise (5 sets of 10 knee extensions with a load equal to 50, 75, and 100% of the maximum pretraining load that could be lifted for 5 sets of 10 repetitions) were quantified pre- and posttraining. MR image contrast shift was quantified by determining QF cross-sectional area (CSA) showing increased spin-spin relaxation time. One repetition maximum increased 14% in the left trained QF and 7% in the right untrained QF. Left QF CSA increased 5%, with no change in right QF CSA. Left QF CSA showing contrast shift was less after each bout of the exercise test posttraining. This was also true, to a lesser extent, for the right QF at the higher two loads. The results suggest that short-term resistance training reduces MR image contrast shift evoked by a given effort, thereby reflecting the use of less muscle to lift the load. Because this response was evident in both trained and contralateral untrained muscle, neural factors are suggested to be responsible.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals PENGARUH PENDEKATAN MELALUI KONSELING INTERPERSONAL TERHADAP RESPON SOSIAL, EMOSIONAL DAN SPIRITUAL PADA PASIEN HIV/AIDS

2020 ◽  
Vol 8 (1) ◽  
pp. 62
Author(s):  
Indah Jayani ◽  
Fatma Sayekti Ruffaida
Keyword(s):  
Opportunistic Infections ◽  
Sampling Technique ◽  
Wilcoxon Test ◽  
P Value ◽  
Social Emotional ◽  
Aids Patients ◽  
Cross Sectional ◽  
Before And After ◽  
The Right ◽  
Hiv Aids

Approach to PLWHA by providing interpersonal counseling is the right thing to do to overcome psychological problems including social, emotional and spiritual aspects of PLWHA. This study aims to look at the effect of interpersonal counseling on social, emotional and spiritual responses in HIV/ AIDS patients. This research is a type of non-experimental research with a cross-sectional approach. The sample is post-test people and tested positive for HIV in the Kediri region, which is 32 with purpossive sampling technique. Data on social, emotional and spiritual responses were obtained based on the results of data recapitulation from the instrument in the form of a questionnaire. The results of the study with the non-parametric Wilcoxon test showed there were differences between social responses of HIV/AIDS patients before and after given interpersonal counseling with p value = 0,000, there were differences between the emotional responses of HIV/AIDS patients before being given interpersonal counseling and after being given counseling with p value = 0,000, and there is a difference between spiritual responses in HIV/AIDS patients before being given interpersonal counseling and after being given interpersonal counseling with p value = 0,000. It can be concluded that interpersonal counseling influences social, emotional and spiritual responses of HIV/AIDS patients. It is recommended that the mentoring of HIV/AIDS patients through interpersonal counseling can continue so as to enhance physiological responses that will have an impact on disease prognosis, prevention of opportunistic infections and reduce mortality rates for HIV patients/ AIDS.

scholarly journals Ankle Taping Effectiveness for the Decreasing Dorsiflexion Range of Motion in Elite Soccer and Basketball Players U18 in a Single Training Session: A Cross-Sectional Pilot Study

2020 ◽  
Vol 10 (11) ◽  
pp. 3759
Author(s):  
Carlos Romero-Morales ◽  
Carlos López-Nuevo ◽  
Carlos Fort-Novoa ◽  
Patricia Palomo-López ◽  
David Rodríguez-Sanz ◽  
...  
Keyword(s):  
Pilot Study ◽  
Range Of Motion ◽  
Elite Athletes ◽  
Weight Bearing ◽  
Training Session ◽  
Ankle Dorsiflexion ◽  
Ankle Sprains ◽  
Basketball Players ◽  
Cross Sectional ◽  
The Right

Ankle sprains have been defined as the most common injury in sports. The aim of the present study was to investigate the ankle taping for the reduction of ankle dorsiflexion range of motion (ROM) and inter-limb in elite soccer and basketball players U18 in a single training session. Methods: A cross-sectional pilot study was performed on 38 male healthy elite athletes divided into two groups: a soccer group and a basketball group. Ankle dorsiflexion ROM and inter-limb asymmetries in a weight-bearing lunge position were assessed in three points: with no-tape, before the practice and immediately after the practice. Results: For the soccer group, significant differences (p < 0.05) were observed for the right ankle, but no differences for the asymmetry variable. The basketball group reported significant differences (p < 0.05) for the right ankle and symmetry. Conclusions: Ankle taping decreased the ankle dorsiflexion ROM in youth elite soccer and basketball players U18. These results could be useful as a prophylactic approach for ankle sprain injury prevention. However, the ankle ROM restriction between individuals without taping and individuals immediately assessed when the tape was removed after the training was very low.

scholarly journals Transient increase in glucose 1,6-bisphosphate in human skeletal muscle during isometric contraction

1989 ◽  
Vol 258 (3) ◽  
pp. 915-918 ◽  
Author(s):  
A D Lee ◽  
A Katz
Keyword(s):  
Isometric Contraction ◽  
Human Skeletal Muscle ◽  
Adenine Nucleotide ◽  
Quadriceps Femoris Muscle ◽  
Muscle Ph ◽  
Before And After ◽  
Ph Decrease ◽  
Fructose 1,6 Bisphosphate ◽  
Adenine Nucleotide Pool ◽  
Femoris Muscle

Changes in glucose 1,6-bisphosphate and regulators of glucose-1,6-bisphosphate synthase and phosphatase during isometric contraction have been determined. Biopsies were obtained from the quadriceps femoris muscle before and after 20 s of contraction and at fatigue. Glucose 1,6-bisphosphate increased by 35% after 20 s of contraction (P less than 0.001) with no further change at fatigue (P greater than 0.05 versus 20 s). Pi, fructose 1,6-bisphosphate and glycerate 3-phosphate, all inhibitors of the synthase, increased significantly during the first 20 s (P less than 0.05-0.001), whereas muscle pH (decrease in which inhibits synthase) decreased continuously. The decrease in the total adenine nucleotide pool, which is stoichiometric with the increase in IMP (an activator of phosphatase), was not significant after 20 s, but was 15% at fatigue (P less than 0.001). The rapid increase in glucose 1,6-bisphosphate, despite increases in the inhibitors of synthase, suggests that the synthase was activated, possibly by the substrate glycerate 1,3-bisphosphate and/or a yet unknown activator(s). The lack of any further change in glucose 1,6-bisphosphate during the latter part of contraction may be due to concomitant activation of the synthase and phosphatase.

A clinical survey about commercial games in lower limb prosthetic rehabilitation

2017 ◽  
Vol 42 (3) ◽  
pp. 311-317 ◽  
Author(s):  
Bita Imam ◽  
William C Miller ◽  
Heather C Finlayson ◽  
Janice J Eng ◽  
Tal Jarus
Keyword(s):  
Lower Limb ◽  
Online Survey ◽  
Weight Bearing ◽  
Prosthetic Rehabilitation ◽  
Nintendo Wii ◽  
Cross Sectional ◽  
Treatment Protocols ◽  
Traditional Therapy ◽  
Wii Fit ◽  
Nintendo Wii Fit

Background: Despite the popularity of commercial games in lower limb prosthetic rehabilitation, data about their prevalence of use as well as therapists’ perspectives about these games are still lacking. Objectives: To learn about the prevalence of use of commercial games in lower limb prosthetic rehabilitation and therapists’ perspectives about these games. Study design: Cross-sectional. Methods: An online survey was sent to physical and occupational therapists across prosthetic rehabilitation facilities in Canada. The survey had questions about the use of commercial games and therapists’ perspectives. Results: Data were collected from 82 therapists. Overall, 46.3% (38/82) reported that they use commercial games; of those, 94.7% (36/38) used the Nintendo Wii Fit. The most reported perceived benefits were the Wii Fit helping to improve weight shifting ( n = 76/82, 92.7%) and balance ( n = 75/82, 91.5%), and being motivating and complementing traditional therapy ( n = 75/82, 91.5%). The most reported perceived barriers/challenges were lack of time and familiarity with the games ( n = 58/82, 70.7%). Conclusion: Commercial games, particularly the Wii Fit, are commonly used in lower prosthetic rehabilitation in Canada. Most of the queried therapists view the Wii Fit positively. Knowledge translation activities and developing standard treatment protocols would be helpful in minimizing the barriers identified in this study. Clinical relevance The Wii Fit is prevalent in lower limb prosthetic rehabilitation in Canada and it is viewed positively by therapists as having the potential to improve balance and weight bearing, making rehabilitation more motivating, and complementing traditional therapy. Future studies should investigate the efficacy of the Wii Fit in prosthetic rehabilitation.

scholarly journals Exercise-induced albuminuria is related to metabolic syndrome

2016 ◽  
Vol 310 (11) ◽  
pp. F1192-F1196 ◽  
Author(s):  
Sharon Greenberg ◽  
Shani Shenhar-Tsarfaty ◽  
Ori Rogowski ◽  
Itzhak Shapira ◽  
David Zeltser ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Binary Logistic Regression ◽  
Cross Sectional Study ◽  
Urinary Albumin ◽  
Binary Logistic Regression Model ◽  
Cross Sectional ◽  
Metabolic Equivalents ◽  
Before And After ◽  
Study Population ◽  
Exercise Induced

Microalbuminuria (MA) is a known marker for endothelial dysfunction and future cardiovascular events. Exercise-induced albuminuria (EiA) may precede the appearance of MA. Associations between EiA and metabolic syndrome (MS) have not been assessed so far. Our aim was to investigate this association in a large sample of apparently healthy individuals with no baseline albuminuria. This was a cross-sectional study of 2,027 adults with no overt cardiovascular diseases who took part in a health survey program and had no baseline MA. Diagnosis of MS was based on harmonized criteria. All patients underwent an exercise test (Bruce protocol), and urinary albumin was measured before and after the examination. Urinary albumin-to-creatinine ratio (ACR) values before and after exercise were 0.40 (0.21–0.89) and 1.06 (0.43–2.69) mg/g for median (interquartile range) respectively. A total of 394 (20%) subjects had EiA; ACR rose from normal rest values (0.79 mg/g) to 52.28 mg/g after exercise ( P < 0.001); this effect was not shown for the rest of the study population. EiA was related to higher prevalence of MS (13.8% vs. 27.1%, P < 0.001), higher metabolic equivalents ( P < 0.001), higher baseline blood pressure ( P < 0.001), and higher levels of fasting plasma glucose, triglycerides, and body mass index ( P < 0.001). Multivariate binary logistic regression model showed that subjects with MS were 98% more likely to have EiA (95% confidence interval: 1.13–3.46, P = 0.016). In conclusion, EiA in the absence of baseline MA is independently related to MS.

scholarly journals Asymmetry and changes in the neuromuscular profile of short-track athletes as a result of strength training

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261265
Author(s):  
Paweł Pakosz ◽  
Anna Lukanova-Jakubowska ◽  
Edyta Łuszczki ◽  
Mariusz Gnoiński ◽  
Oscar García-García
Keyword(s):  
Strength Training ◽  
Lower Limb ◽  
Female Athletes ◽  
Lower Limbs ◽  
Lower Limb Muscles ◽  
Limb Muscles ◽  
Before And After ◽  
Monthly Period ◽  
Track Athletes ◽  
The Right

Background The purpose of this study was to identify the biomedical signals of short-track athletes by evaluating the effects of monthly strength training on changes in their neuromuscular profile, strength, and power parameters of the lower limb muscles. Muscle asymmetry, which can cause a risk of injury, was also evaluated. Methods and results This study involved female athletes, age 18.8 ± 2.7 years, with a height of 162 ± 2.4 cm, and weight of 55.9 ± 3.9 kg. Before and after the monthly preparatory period prior to the season, strength measurements were assessed through the Swift SpeedMat platform, and reactivity of the lower limb muscles was assessed with tensiomyography (TMG). The athletes were also tested before and after the recovery training period. In the test after strength training, all average countermovement jump (CMJ) results improved. Flight time showed an increase with a moderate to large effect, using both legs (5.21%). Among the TMG parameters, time contraction (Tc) changed globally with a decrease (-5.20%). Changes in the results of the test after recovery training were most often not significant. Conclusion A monthly period of strength training changes the neuromuscular profile of short-track female athletes, with no significant differences between the right and left lower limbs.

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